It’s an uphill struggle for those with so-called invisible difficulties (people with conditions on the autistic spectrum, for example,) to achieve mainstream representation or indeed capture the attention of broadcasters, newspaper editors, politicians and the public.

So imagine the challenge for those with more visible differences.

If you see facial disfigurement in movies, its usually a handy hint just in case you have trouble figuring out the baddie (think Nightmare on Elm Street’s Freddie Kreuger and just about every Bond villain). Trying to see if I could disprove this theory, I randomly remembered Liam Neeson in Darkman – scarred, with a grudge, ultimately fighting for justice – but then looked up the tagline” “hideously scarred and mentally unstable scientist seeks revenge against the crooks who made him like that”. Ouch.

Movie memo to kids (they might not know Freddie Kreuger but you can be sure they know Batman’s The Joker or Harry Potter’s Voldemort): look bad on the outside, and you’re bad inside.

Today, Changing Faces, the charity for people and families whose lives are affected by appearance-altering conditions, marks or scars, launches a nationwide film campaign. Please watch it, it’s powerful, elegantly produced and only a minute long.

You might already have spotted the charity’s poster campaign not so long ago which aimed to stop people in their tracks long enough to make them think (instead of simply staring). Today’s Face Equality on Film campaign, it is hoped, will go some way towards tackling the prejudice and crass assumptions experienced by people with facial disfigurement.

The campaign calls for balanced portrayals of people with disfigurements on screen and the film, which will be shown in 750 Odeon cinemas, invites audiences to challenge their assumptions about Leo Gormley, a man with burn scars. It also stars Downton Abbey actor Michelle Dockery.

As a teenager in the ’80s, my first foray into the mind-boggling world of skincare and “beauty” products involved a desperate desire to cover barely perceptible blemishes, inspired by the seemingly zit-free stars on my Smash Hits front cover. But since, then the concept of “beauty” has become even more extreme, and digital wizardry can clear imperfections in the blink of a heavily-made-up eye.

I’m conscious that my seven-year-old daughter, for example, is growing up in a media environment dominated by images of identikit, airbrushed, photoshopped lovelies projecting an unobtainable and flawless version of “looking good”.

In a world where older women are elbowed off the television news because their faces, rather than their news judgement, start to sag, what hope for those whose features even further removed from what is deemed be aesthetically pleasing? Changing Faces has already worked with Channel Five news to shatter such stereotypes.

But if women, ethnic minorities and people with disabilities are under-represented in television, then people whose differences are more obvious are, ironically, even more invisible.

And if facial differences feature on television, they do so in a medical capacity, in documentaries that present abnormality as something to be gawped at or “put right”. While the concept behind The Undateables might have been well-intentioned, it was the title of the show that put me off.

As Changing Faces’ chief executive James Partridge said in response to that Channel 4 series: “TV series with derisory titles makes life just that bit more difficult – it’s so unnecessary and it’s unfair. Very good factual and sensitive documentaries on disfigurement-related topics are frequently spoiled by offensive titles such as ‘Freak show family’, ‘The man with tree trunks for legs’ and ‘Bodyshock’. They are contrived to attract audiences but actually label the human being in the film in a sensationalist and voyeuristic way, treating him or her as an object rather than a person.”

At the risk of getting sidetracked down this road, I remember gritting my teeth a few years ago to get past the utterly ludicrous title of The Strangest Village in Britain. It was, was in fact a sensitive portrayal of life at Camphill’s Botton village which featured much of the good support that has made a difference to my family’s life – not that you’d know that from the objectionable title.

Back to today’s campaign launch; a YouGov survey of 1,741 adults commissioned by the charity last month found that bad teeth, scars, burns and other conditions affecting the face are viewed as the most common indicators of an evil film character. According to the poll, ethnic minorities, bald and disabled people are all thought to be portrayed in more diverse ways than those with disfigurements.

Responding to the poll, 66% said people with bad teeth mainly play evil characters and 48% said that people with conditions altering their appearance mainly play evil characters. Meanwhile, 30% said that bald people mainly play evil such roles compared to 13% who felt those from ethnic minorities mainly portrayed bad characters. Interestingly, 6% said that people with physical disabilities (in a wheelchair or have missing limbs) mainly play evil characters.

Partridge adds of today’s campaign: “It would seem as if all the film industry has to do to depict evil and villainy is apply a scar or a prosthetic eye socket or remove a limb and every movie goer knows that it’s time to be suspicious, scared or repulsed…Freddie Krueger, Scarface and Two-Face are just some of the names that our clients get called at school, on the street and at work. They have to put up with people laughing at them, recoiling, running away or staring in disbelief that they can and do live a normal life.”

* You can sign the charity’s online petition demanding an end to the stigma reinforced on screen.